Oscillatory circuits



March 25, 1930. A. MEISSNER 1,751,592

OSCILLATORY CIRCUITS Filed April 10, i925 l me: mm; 25: mm

mm/ or m MUM 14 001M575? INVENTOR ALEXANDER MEISSNER ATTORNEY Patented Mar. .25, 1930 UNITED. STATES PA'TE N ALEXANDER m'nrssnnn, 0F BERLIN, GERMANY, ASSIGNOR To. ensntnscnnr'rrnn DBAI-ITLOSE TELEGRAfPI-IIE M. B. H. HALLESO'HES, or BERLIN, GERMANY' OSCILLATOR? fc'rncu'rrs'"v Application filed April 10, 1925, Serial No. 22,025, eta in 'Germany Ap ril 25,1924.

My invention relates to high frequency signalling systems and more particularly to a new anduseful inductance coil and system thru the winding thereof and which will.

have low hysteresis and eddy current losses.

Another object is to provide method and means for using the coil which will be eflicient in operation.

Other objects will be apparent from the following description and claims when considered with the accompanying drawing.

The use of coils provided with iron cores in high frequency systems is known. For the purpose of reducing iron losses, it is Well known to make the cores of subdivided iron. It has been shown that with cores consisting of iron wires a special effect obtains, for, in the presence of such extremely fine transverse subdivision without interruption of the flux path in the direction of the flux the magnetization is large, while the eddy-current losses become'very low. The use of such coils is known for the purposes of high frequency transmitters employing frequency transformers;

The inductance of such coils, at a given strength of current, undergoes very considerable changes, since the permeability at .a

certain strength of current experiences a very sudden rise.- Now, the present invention utilizes this effect of strong rise in permeability when such thin wires are used, in such a manner that coils provided with cores of iron wires are employed for receiving purposes, the wire having a diameter smaller than of one millimeter and made from ferro-nickel alloys. The best alloy known to me at the present time for this purpose is the so-called permalloy containing about 80 percent nickel and 20 percent iron.

For instance, a coil equipped with an iron core of the kind described can be used as an inductance coil contained in an oscillation circuit, with the saturation of the coil being so chosen that for the strength of the incoming current the inductance of the coil circuit II has coupling coil 2, inductance A,

just corresponds to the resonance condition. Upon the arising of stronger disturbances.

and oscillations, the permeability changes considerably and therefore also the inductance, with the consequence thatmarked'detuning of the circuit is produced. In this 1 manner, as can be seen, a sort'of amplitude selection s attainable.

"In'the various figures ofthe drawing If have shown a tlon. I

preferred form of my inven- Fi 1 shows the circuit arran ement.

- Figs. 2 and 3 show modified forms ofthe Wire core wherein "Fig. 2"shows a closed ringformand- Fig. 3 showsan open ring with a constant of 'Wires 3'ofvery small diameter, preferv ably less than one tenth 'ofone millimeter and a winding 4. The "material from which the Wires are made is,according to the invention, an alloy consisting of about percent nickel and 20percent iron. The tuned thesignal responsive means and a-. tuning condenser 5 all in series.

It will easily be seen that if the circuit II is tuned to resonance at a certain fre'- quency, the exact amount of current must flow thru' circuit II to give the coil A its proper inductance.

The arrangements shown in Figs. 2 and 3 are modified forms whichthe wire cores shown in Fig. 1 may assume.

'The use of coils of the kind described is convenient also for the purposes of coupling various parts of the receiving apparatus. Coils of the same sort could also be used in reception for frequency raising, and also for frequency reduction. It is thus feasible to change the incoming high frequency Waves into low frequency by multiple reduction of frequency.

Having described my invention,I claim:

1. An oscillatory circuit resonant to a desired signal of a predetermined current strength adapted to be used with a signal responsive means, including a tuning condenser and an inductance device connected 7 therewith, said inductance device having a ferro-nickel core so constructed as to reduce eddy current losses to a low value and being adapted to bring said circuit to a non-resonant condition upon an increase of current 10 strength beyond that of said predetermined strength.

2. An oscillatory circuit resonant to a desired signal of a predetermined current strength including a tuning condenser and an inductance device connected in series therewith, said device having a core composed of permalloy Wires for bringing said circuit to a non-resonant condition upon an increase of current strength beyond said predetermined strength.

3. An oscillatory circuit comprising means to tune it to a desired signal of a predetermined current strength, and an inductive means including a magnetic, metallic core for bringingsaid circuit to anon-resonant condition upon an increase of current strength )eyond said predetermined strength, said core being so constructed as to maintain eddy current losses at a low value.

l. An oscillatory circuit resonant to a de-' sired signal of a predetermined current strength adapted to be used With a signal responsive means, including a tuning condenser, an inductance device connected thereto, said device having a permalloy core for bringing the circuit to a non-resonant condition upon an increase of current strength beyond that of said predetermined strength, said core being constructed to maintain eddy m current losses at a low value.

ALEXANDER MEISSNER. 

